Abstract

A series of salts of the radical ion TCNQ were prepared by standard organic techniques or by controlled electrocrystallisation and their three-dimensional crystal structures were determined by single crystal X-ray diffractometry. The crystallisation of the two-phase system found in 1,2-bis(1-ethyl-4-pyridinio)ethene (TCNQ)4 was studied using a.c. conductivity techniques. The results showed phase formation to be dependent upon both concentration and cooling rate, and no evidence was found for a third phase possessing a metallic d.c. solid state conductivity.